[Chaulmoogra oil as scientific knowledge: the construction of a treatment for leprosy]. / O óleo de chaulmoogra como conhecimento científico: a construção de uma terapêutica antileprótica.

The article investigates how knowledge of medicinal plants and related treatment practices are assimilated and transformed. Taking as its focus the use of chaulmoogra oil to treat leprosy, it examines how information on this plant was incorporated and transformed into scientifically validated knowledge when 'Brazilian chaulmoogra' came onto the scene. Pointing to the addition of chaulmoogra byproducts to the Instituto Oswaldo Cruz's production agenda in the 1920s, the study establishes links between productive processes and relates these to the period's scientific context. From the late nineteenth century until the 1940s, chaulmoogra oil was the great hope in efforts to cure leprosy. During this period, chaulmoogric treatment earned a place as scientific knowledge thanks to research studies conducted in laboratories throughout the Western world.

[The people of the black waters: the Amazon caboclo of the Negro river]. / O povo das águas pretas: o caboclo amazônico do rio Negro.

The article constructs a historically contextualized description of the people who live along the Negro river, a Brazilian affluent in the Amazon basin. Drawing on information about the daily social experience of the participants from the dawn of the twentieth century through the mid-1990s, the processes by which the population and communities took shape are identified. On the Negro river, contact between Brazilian society and the autochthonous, catechized indigenous groups living there was determinant in shaping the territory's caboclo identity. Starting in the last quarter of the nineteenth century, this nomenclature took root and entered the popular lexicon. Extractivist activities played a major role in spreading the term, within a context where the predominant social relations derived from the 'cultura do barracão'.